When I was using a master slave integrated host, when I quickly disconnected the connection and then set up the connection immediately, it was found that the original disconnected connection could also receive data, that is to say, the new connection could receive data, and the old disconnected connection could also receive data.
The host project I used is ble_central_and_peripheral\experimental\ble_app_hrs_rscs_relay
The slave Engineering I used is nRF5_SDK_14.2.0_17b948a\examples\ble_peripheral\ble_app_uart\pca10040